fix(deploy): 端到端跑通编译二进制 + docker compose

端到端验证时发现 4 处细节，一起补上：

1. bin.ts 漏了 default: 'serve'——CMD ["./server"] 会直接吐 help 而
   不是起服务（在 compose 里 app 立刻 exit）。citty 原生支持 default
2. Dockerfile 在 bun install 之前就要 COPY patches/，否则 package.json
   的 patchedDependencies 找不到补丁文件，install 失败
3. drizzle/ 目录在仓库里必须存在（带 .gitkeep），否则 Dockerfile 末尾
   COPY drizzle/ 到运行镜像会失败
4. migrate.ts 之前只检查 ./drizzle 目录是否存在就跳过——空目录时仍会
   进到 drizzle 的 readMigrationFiles，报 Can't find meta/_journal.json。
   改成检查 meta/_journal.json 是否存在，更准确地区分"还没生成过迁移"
   与"有迁移待应用"

验证路径：
- docker compose up -d --build → migrate 完成退出 → app 健康
- curl /api/spec.json → 200，OpenAPI 文档含 todo.{list,create,update,remove}

Dockerfile

@@ -3,6 +3,7 @@ FROM oven/bun:1.3.13 AS build
 WORKDIR /app
 
 COPY package.json bun.lock ./
+COPY patches ./patches
 RUN bun install --frozen-lockfile
 
 COPY . .

bin.ts

@@ -11,6 +11,7 @@ const main = defineCommand({
     version,
     description: 'Fullstack server binary (default subcommand: serve)',
   },
+  default: 'serve',
   subCommands: {
     serve: () => import('./src/cli/serve').then((m) => m.default),
     migrate: () => import('./src/cli/migrate').then((m) => m.default),

src/cli/migrate.ts

@@ -2,6 +2,7 @@ import { existsSync } from 'node:fs'
 import { defineCommand } from 'citty'
 
 const MIGRATIONS_FOLDER = './drizzle'
+const JOURNAL = `${MIGRATIONS_FOLDER}/meta/_journal.json`
 
 export default defineCommand({
   meta: {
@@ -9,8 +10,8 @@ export default defineCommand({
     description: 'Apply pending database migrations from ./drizzle',
   },
   async run() {
-    if (!existsSync(MIGRATIONS_FOLDER)) {
+    if (!existsSync(JOURNAL)) {
-      console.log(`No ${MIGRATIONS_FOLDER} directory; nothing to apply (use db:push in dev).`)
+      console.log(`No migrations found at ${MIGRATIONS_FOLDER} (run \`bun run db:generate\` to create some).`)
       return
     }